| /* |
| * Copyright 2016-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license. |
| */ |
| |
| package kotlinx.coroutines.experimental.internal |
| |
| import kotlinx.coroutines.experimental.TestBase |
| import org.junit.Assert.* |
| import org.junit.Test |
| import java.util.* |
| import java.util.concurrent.atomic.AtomicInteger |
| import kotlin.concurrent.thread |
| |
| /** |
| * This stress test has 6 threads adding randomly first to the list and them immediately undoing |
| * this addition by remove, and 4 threads removing first node. The resulting list that is being |
| * stressed is very short. |
| */ |
| class LockFreeLinkedListShortStressTest : TestBase() { |
| data class IntNode(val i: Int) : LockFreeLinkedListNode() |
| val list = LockFreeLinkedListHead() |
| |
| val TEST_DURATION = 5000L * stressTestMultiplier |
| |
| val threads = mutableListOf<Thread>() |
| val nAdderThreads = 6 |
| val nRemoverThreads = 4 |
| val completedAdder = AtomicInteger() |
| val completedRemover = AtomicInteger() |
| |
| val undone = AtomicInteger() |
| val missed = AtomicInteger() |
| val removed = AtomicInteger() |
| |
| @Test |
| fun testStress() { |
| println("--- LockFreeLinkedListShortStressTest") |
| val deadline = System.currentTimeMillis() + TEST_DURATION |
| repeat(nAdderThreads) { threadId -> |
| threads += thread(start = false, name = "adder-$threadId") { |
| val rnd = Random() |
| while (System.currentTimeMillis() < deadline) { |
| var node: IntNode? = IntNode(threadId) |
| when (rnd.nextInt(3)) { |
| 0 -> list.addLast(node!!) |
| 1 -> assertTrue(list.addLastIf(node!!, { true })) // just to test conditional add |
| 2 -> { // just to test failed conditional add |
| assertFalse(list.addLastIf(node!!, { false })) |
| node = null |
| } |
| } |
| if (node != null) { |
| if (node.remove()) |
| undone.incrementAndGet() |
| else |
| missed.incrementAndGet() |
| } |
| } |
| completedAdder.incrementAndGet() |
| } |
| } |
| repeat(nRemoverThreads) { threadId -> |
| threads += thread(start = false, name = "remover-$threadId") { |
| while (System.currentTimeMillis() < deadline) { |
| val node = list.removeFirstOrNull() |
| if (node != null) removed.incrementAndGet() |
| |
| } |
| completedRemover.incrementAndGet() |
| } |
| } |
| threads.forEach { it.start() } |
| threads.forEach { it.join() } |
| println("Completed successfully ${completedAdder.get()} adder threads") |
| println("Completed successfully ${completedRemover.get()} remover threads") |
| println(" Adders undone ${undone.get()} node additions") |
| println(" Adders missed ${missed.get()} nodes") |
| println("Remover removed ${removed.get()} nodes") |
| assertEquals(nAdderThreads, completedAdder.get()) |
| assertEquals(nRemoverThreads, completedRemover.get()) |
| assertEquals(missed.get(), removed.get()) |
| assertTrue(undone.get() > 0) |
| assertTrue(missed.get() > 0) |
| list.validate() |
| } |
| } |